To cite package ‘smacofx’ in publications use:

  Rusch T, de Leeuw J, Chen L, Mair P (2024). _smacofx: Flexible
  Multidimensional Scaling and 'smacof' Extensions_. R package version
  1.71-1, <https://r-forge.r-project.org/projects/stops>.

A BibTeX entry for LaTeX users is

  @Manual{,
    title = {smacofx: Flexible Multidimensional Scaling and 'smacof' Extensions},
    author = {Thomas Rusch and Jan {de Leeuw} and Lisha Chen and Patrick Mair},
    year = {2024},
    note = {R package version 1.71-1},
    url = {https://r-forge.r-project.org/projects/stops},
  }